The terms conservation and preservation are frequently conflated outside of the academic, scientific, and professional literatures. The US National Park Service offers the following explanation of the important ways in which these two terms represent very different conceptions of environmental protection ethics:

″Conservation and preservation are closely linked and may indeed seem to mean the same thing. Both terms involve a degree of protection, but how that is protection is carried out is the key difference. Conservation is generally associated with the protection of natural resources, while preservation is associated with the protection of buildings, objects, and landscapes. Put simply, conservation seeks the proper use of nature, while preservation seeks protection of nature from use.

During the environmental movement of the early 20th century, two opposing factions emerged: conservationists and preservationists. Conservationists sought to regulate human use while preservationists sought to eliminate human impact altogether.″[1]

To protect sea life from extinction due to overfishing or climate change is another commonly stated goal of conservation — ensuring that "some will be available for future generations" to continue a way of life.

The consumer conservation ethic is sometimes expressed by the four R's: " Rethink, Reduce, Recycle, Repair" This social ethic primarily relates to local purchasing, moral purchasing, the sustained, and efficient use of renewable resources, the moderation of destructive use of finite resources, and the prevention of harm to common resources such as air and water quality, the natural functions of a living earth, and cultural values in a built environment.

The principal value underlying most expressions of the conservation ethic is that the natural world has intrinsic and intangible worth along with utilitarian value — a view carried forward by the scientific conservation movement and some of the older Romantic schools of ecology movement.

In the United States of America, the year 1864 saw the publication of two books which laid the foundation for Romantic and Utilitarian conservation traditions in America. The posthumous publication of Henry David Thoreau's Walden established the grandeur of unspoiled nature as a citadel to nourish the spirit of man. From George Perkins Marsh a very different book, Man and Nature, later subtitled "The Earth as Modified by Human Action", catalogued his observations of man exhausting and altering the land from which his sustenance derives.

Distinct trends exist regarding conservation development. While many countries' efforts to preserve species and their habitats have been government-led, those in the North Western Europe tended to arise out of the middle-class and aristocratic interest in natural history, expressed at the level of the individual and the national, regional or local learned society. Thus countries like Britain, the Netherlands, Germany, etc. had what we would today term NGOs — in the shape of the RSPB, National Trust and County Naturalists' Trusts (dating back to 1889, 1895 and 1912 respectively) Natuurmonumenten, Provincial conservation Trusts for each Dutch province, Vogelbescherming, etc. — a long time before there were national parks and national nature reserves. This in part reflects the absence of wilderness areas in heavily cultivated Europe, as well as a longstanding interest in laissez-faire government in some countries, like the UK, leaving it as no coincidence that John Muir, the Scottish-born founder of the National Park movement (and hence of government-sponsored conservation) did his sterling work in the USA, where he was the motor force behind the establishment of such NPs as Yosemite and Yellowstone. Nowadays, officially more than 10 percent of the world is legally protected in some way or the other, and in practice private fundraising is insufficient to pay for the effective management of so much land with protective status.

Protected areas in developing countries, where probably as many as 70–80 percent of the species of the world live, still enjoy very little effective management and protection. Some countries, such as Mexico, have non-profit civil organizations and land owners dedicated to protect vast private property, such is the case of Hacienda Chichen's Maya Jungle Reserve and Bird Refuge[4] in Chichen Itza, Yucatán. The Adopt A Ranger Foundation has calculated that worldwide about 140,000 rangers are needed for the protected areas in developing and transition countries. There are no data on how many rangers are employed at the moment, but probably less than half the protected areas in developing and transition countries have any rangers at all and those that have them are at least 50% short This means that there would be a worldwide ranger deficit of 105,000 rangers in the developing and transition countries.

One of the world's foremost conservationists, Dr. Kenton Miller, stated about the importance of rangers: "The future of our ecosystem services and our heritage depends upon park rangers. With the rapidity at which the challenges to protected areas are both changing and increasing, there has never been more of a need for well prepared human capacity to manage. Park rangers are the backbone of park management. They are on the ground. They work on the front line with scientists, visitors, and members of local communities."

Adopt A Ranger,[5] fears that the ranger deficit is the greatest single limiting factor in effectively conserving nature in 75% of the world. Currently, no conservation organization or western country or international organization addresses this problem. Adopt A Ranger has been incorporated to draw worldwide public attention to the most urgent problem that conservation is facing in developing and transition countries: protected areas without field staff. Very specifically, it will contribute to solving the problem by fund raising to finance rangers in the field. It will also help governments in developing and transition countries to assess realistic staffing needs and staffing strategies.

Others, including Survival International, have advocated instead for cooperation with local tribal peoples, who are natural allies of the conservation movement and can provide cost-effective protection.[6]